Remove leftover debug code from Box class

[getsyash]

There is a commented-out debug statement // print_r( $this ); // Uncomment to print all boxes. in the Box::parse() method on the file /wp-includes/class-box.php

This appears to have been used during development for debugging purposes. While it's currently commented out and doesn't affect execution, it's generally a good practice to remove unused debug code from production files to keep the codebase clean and focused.

Removing this line would help improve readability and align with WordPress coding standards for maintainable code.

Trac ticket: https://core.trac.wordpress.org/ticket/63478

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